Field of the Invention
The present disclosure relates to a hydraulic ship lift with anti-overturning capability and a method for using the same.
Description of the Related Art
Hydraulic ship lifts are used to raise or lower a ship with the aid of hydraulic power. In use, the ship reception chamber of the hydraulic ship lift often suffers unbalanced loads and tends to tilt. This leads to the shift of the gravity center of the ship, and may lead to catastrophic overturn.
As shown in FIG. 1 and FIG. 2, when the ship reception chamber is in a water-free operating state, regardless of whether it is tilted or horizontal, the gravity centers of the loads and the ship reception chamber are unchanged, and the loads of the ship reception chamber acting on the hoisting points are essentially the same (F1=F2).
As shown in FIG. 3 and FIG. 4, when the ship reception chamber is filled with water and stays horizontal, the gravity centers of the ship reception chamber and the water body load are located at the center of the ship reception chamber, and the loads of the ship reception chamber acting on the hoisting points are essentially the same (F1=F2); however, when the ship reception chamber is tilted, the water body load of the ship reception chamber moves, so that the gravity centers of the ship reception chamber and the water body load change, and accordingly the loads of the ship reception chamber acting on the hoisting points change (F1 is larger than F2), further increasing the tilt of the ship reception chamber. This situation constitutes a positive feedback phenomenon which poses a risk of overturning the ship lift with the ship.